Meteor showers to make sky sparkle on Aug 12
The night sky will be streaked with light in a celestial spectacle put up by the most famous Perseids meteor showers.delhi Updated: Aug 07, 2008 15:54 IST
The night sky will be streaked with light in a celestial spectacle put up by the Perseids meteor showers on August 12.
Sky gazers can look out for it before dawn when over 100 meteors will sparkle in the night sky.
"Perseids are the most famous and beautiful of all meteor showers that approach from the horizon. They are long, slow and colourful," Nehru Planetaruim director N Rathnashree told IANS.
"One can see streaks of light in the sky, javelin-shaped in appearance. They will last for a fraction of a second and will almost be as bright as most stars," Rathnashree said. <b1>
"For a while the beautiful Moon will interfere with the Perseids, the lunar glare wiping out all but the brightest meteors.
The situation will reverse itself at 2 am on August 12, when the Moon sets and leaves behind a dark sky for the Perseids.
"The shower will surge into the darkness, peppering the sky with perhaps hundreds of meteors until dawn," Rathnashree said.
The Perseids meteor shower occurs every year between July 25 and August 18, with a peak on August 12. It has its origin in the constellation Perseus.
As comets move about their orbits, they leave a trail of dusty and rocky debris. When the Earth passes through the comets' orbit, the debris are attracted towards it because of gravity and burn due to the friction experienced during entry into the atmosphere, leading to a meteor shower.
"Meteor showers usually have around 100-120 meteors. The typical number of meteors that can be seen per hour at its peak is about 70, which is 10 times the rate of random meteors," said Chandra Bhushan Devgun, director of the Science Popularisation Association of Communicators & Educators.
"The source of the shower is Comet Swift-Tuttle. Although the comet is far away, currently located beyond the orbit of Uranus, a trail of debris from the comet stretches all the way back to Earth.
"Crossing the trail in August, the Earth will be pelted by specks of comet dust hitting the atmosphere at 132,000 mph. At that speed, even a flimsy speck of dust makes a vivid streak of light when it disintegrates," Devgun said.
Records of Perseids activity date back to 36 AD. In 1839, German astronomer Eduard Heis was the first to take a meteor count and discovered that Perseids had a maximum rate of around 160 meteors per hour.